Is interactive technology a relevant and effective enrichment for captive great apes?

Health and Welfare Benefits of Computerized Cognitive Enrichment in California Sea Lions (Zalophus californianus) at the US Navy Marine Mammal Program

Cognitive enrichment is becoming more prevalent in professional marine mammal facilities. Research with dolphins has suggested that such enrichment provides more welfare benefits than enrichment that does not incorporate cognitive challenge. However, there is little research supporting the use of cognitive enrichment as a means to improve the welfare of sea lions. Recently, a novel form of technological cognitive enrichment, the Enclosure Video Enrichment (EVE) system, was introduced to a population of California sea lions at the US Navy's Marine Mammal Program as a means to enhance welfare. Two of the initial focal animals introduced to EVE were selected based on their health history and the possible benefits of cognitive enrichment in improving health measures. To evaluate this, information regarding the animals' consumption of their offered diet was compared to other animals in the population of similar age and the absence of a similar health history. Subsequently, the total diet consumption of the targeted animals was evaluated in the two years prior to the introduction to EVE and compared to the total diet consumption during the initial 2 years of regular EVE sessions. There was a significant decrease in the number of days in which the sea lions did not consume their entire offered diet in the two years after implementing regular EVE sessions, an increase in participation and performance of voluntary husbandry behaviors, and a reduction in the number of days animals were clinically ill. This study provides evidence of cognitive enrichment as a management tool to improve animal health and welfare as well as performance in training sessions.

An Ecological and Neural Argument for Developing Pursuit-Based Cognitive Enrichment for Sea Lions in Human Care

While general enrichment strategies for captive animals attempt to elicit variable and species-typical behaviors, approaches to cognitive enrichment have been disappointingly one-size-fits-all. In this commentary, we address the potential benefit of tailoring cognitive enrichment to the "cognitive niche" of the species, with a particular focus on a reasonably well-studied marine carnivore, the sea lion. Sea lions likely share some cognitive evolutionary pressures with primates, including complex social behavior. Their foraging ecology, however, like that of many terrestrial carnivores, is based on the rapid and behaviorally flexible pursuit of avoidant prey. Unlike terrestrial carnivores, sea lions carry out this pursuit in a truly fluid three-dimensional field, computing and executing sensorimotor transformations from any solid angle to any other. The cognitive demands of flexible prey pursuit are unlikely to be fully elicited by typical stationary puzzle box style foraging enrichment devices or screen-based interactive games. With this species, we recommend exploring more water-based movement activities generally, and complex pursuit challenges specifically.

Cognitive Foraging Enrichment (but Not Non-Cognitive Enrichment) Improved Several Longer-Term Welfare Indicators in Bottlenose Dolphins

Bottlenose dolphins are the most common cetacean kept globally in zoos and aquaria (hereafter zoos), and are gregarious animals with a mostly opportunistic, generalist feeding strategy in the wild. In zoos, they have limited to no opportunities to express natural foraging behaviours as they receive their daily food ration of dead fish in a series of training sessions. Enrichment provision has increased in recent years, but items are still predominantly simple and floating in nature, and do not always target the animals' problem-solving or food-acquisition behaviours. These discrepancies run concurrently with the intense debate about dolphin welfare in zoos and how to improve it. The current study used a within-subject design on 11 bottlenose dolphins at Kolmårdens Djurpark and measured how several welfare indicators differed between two treatments of "cognitive" and "non-cognitive" food-based enrichment. The treatments were provided on an alternating basis for eight consecutive weeks: during cognitive enrichment weeks, the animals received items which stimulated their problem-solving and foraging behaviours, and during non-cognitive enrichment weeks, they received simple items paired with fish (to eliminate bias due to food value). Data were taken related to several multidisciplinary welfare parameters during enrichment provision and training sessions, and to activity budget behaviours throughout the week. During the cognitive as opposed to non-cognitive enrichment weeks, the dolphins engaged more with the enrichment, were more motivated to participate in training sessions and performed less anticipatory and stereotypic behaviours, suggesting that cognitive enrichment improved several indicators of bottlenose dolphin welfare. Valuable lines of further investigation would be to understand how individual differences and different types of cognitive enrichment impact potential welfare benefits. Our results suggest that enrichment items promoting cognitive foraging behaviours may improve dolphin welfare, and therefore zoos might prioritise giving cognitive enrichment to this species as well as considering the same for other species with similar cognitive skills and foraging ecologies.

An Evaluation of Ethograms Measuring Distinct Features of Enrichment Use by Captive Chimpanzees (Pan troglodytes)

Simple Summary

Environmental enrichment for chimpanzees is important in order to minimize boredom and stress in captivity and to provide opportunities to engage in species-typical behaviors. However, few studies have investigated potential associations between enrichment objects, manipulation behaviors, and social contexts, nor have they examined if individual chimpanzees vary in their enrichment object preferences. In the current study, three ethograms were used to code the use of enrichment objects, engagement in manipulation behaviors, and social contexts of enrichment use of captive chimpanzees (Pan troglodytes). Data mining from a video archive consisting of 2054 videos collected over a decade allowed the ethograms to be applied to 732 min and 58 s of videos. Some enrichment objects were more often associated with specific manipulation behaviors and social contexts, indicating that enrichment objects might serve distinct social and behavioral purposes. The chimpanzees differed in their enrichment object preferences, suggesting that caregivers of captive chimpanzees should consider individual needs when providing enrichment in order to improve chimpanzees’ experiences in captivity. Finally, the majority of enrichment object use and manipulation behaviors were able to be categorized, indicating that our ethograms were largely effective in coding enrichment use.

Abstract

Environmental enrichment provides mental stimulation and minimizes abnormal behaviors in captive animals. In captive chimpanzees, individual animals may vary in the ways in which they benefit from enrichment or use enrichment devices, so investigating nuances in enrichment use may improve the welfare of captive chimpanzees. In the current study, three ethograms measuring distinct features of enrichment use (i.e., enrichment object, manipulation behavior, and social context) were evaluated by coding videos of captive chimpanzees (Pan troglodytes) at Chimpanzee Sanctuary Northwest in Cle Elum, WA. A total of 732 min and 58 s of video footage was coded from a larger video archive (i.e., 2054 videos) of enrichment use that spanned a decade. A principal component analysis (PCA) revealed that different categories of enrichment objects were more often associated with specific manipulation behaviors and social contexts, suggesting that enrichment objects might fulfill different behavioral and social needs in captivity. Specifically, toy objects were associated with active tactile behaviors in affiliative contexts while oral behaviors were used with foraging objects in solitary contexts. Additionally, individual chimpanzees showed unique preferences for enrichment objects, indicating that caregivers of captive chimpanzees should consider individual needs instead of a “one size fits all” approach to enrichment provisions.

Cognitive enrichment in a social setting: assessing the use of a novel food maze in sanctuary-housed chimpanzees

Foraging devices are effective enrichment tools for non-human primates, as they provide both cognitive and manipulative stimulation that may enhance these animals’ welfare. We assessed the behavioral effects of a novel tool-based enrichment on 14 chimpanzees (Pan troglodytes) housed at Fundació Mona (Girona, Spain). The device consisted of a vertical maze filled with food rewards, which chimpanzees could extract by using tools. We conducted behavioral observations in two conditions over an approximately 2.5-month period: when the food maze was loaded (12 enrichment days), and when it was empty (12 baseline days). Data were collected using 2-min scan sampling and untimed-event focal sampling during two daily sessions of 80 min each. We expected that the chimpanzees’ interest in the enrichment would decrease over time, but that its use would be linked to an increase in the occurrence of species-typical behaviors, a reduction in negative indicators of welfare, and changes in social behaviors. We found that participation widely varied among subjects, being higher in females and decreasing through time. Furthermore, participation was linked to an increase in tool use and a decrease in inactivity, but also to an increase in aggression-related behaviors. In contrast, participation had no effect on the occurrence of abnormal behaviors, social proximity or affiliation-related behaviors. Finally, we detected an increase in self-directed behaviors only when subjects actively interacted with the device. We conclude that, in future studies, these types of devices should be evaluated for longer periods of time and more attention should be paid to individuals’ preferences and abilities.

Welfare Through Competence: A Framework for Animal-Centric Technology Design

Digital technologies offer new ways to ensure that animals can lead a good life in managed settings. As interactive enrichment and smart environments appear in zoos, farms, shelters, kennels and vet facilities, it is essential that the design of such technologies be guided by clear, scientifically-grounded understandings of what animals need and want, to be successful in improving their wellbeing. The field of Animal-Computer Interaction proposes that this can be achieved by centering animals as stakeholders in technology design, but there remains a need for robust methods to support interdisciplinary teams in placing animals' interests at the heart of design projects. Responding to this gap, we present the Welfare through Competence framework, which is grounded in contemporary animal welfare science, established technology design practices and applied expertise in animal-centered design. The framework brings together the “Five Domains of Animal Welfare” model and the “Coe Individual Competence” model, and provides a structured approach to defining animal-centric objectives and refining them through the course of a design project. In this paper, we demonstrate how design teams can use this framework to promote positive animal welfare in a range of managed settings. These much-needed methodological advances contribute a new theoretical foundation to debates around the possibility of animal-centered design, and offer a practical agenda for creating technologies that support a good life for animals.

Manipulating actions: a selective two‐option device for cognitive experiments in wild animals

Advances in biologging technologies have significantly improved our ability to track individual animals' behaviour in their natural environment. Beyond observations, automation of data collection has revolutionized cognitive experiments in the wild. For example, radio-frequency identification (RFID) antennae embedded in 'puzzle box' devices have allowed for large-scale cognitive experiments where individuals tagged with passive integrated transponder (PIT) tags interact with puzzle boxes to gain a food reward, with devices logging both the identity and solving action of visitors. Here, we extended the scope of wild cognitive experiments by developing a fully automated selective two-option foraging device to specifically control which actions lead to a food reward and which remain unrewarded. Selective devices were based on a sliding-door foraging puzzle, and built using commercially available low-cost electronics. We tested it on two free-ranging PIT-tagged subpopulations of great tits Parus major as a proof of concept. We conducted a diffusion experiment where birds learned from trained demonstrators to get a food reward by sliding the door either to the left or right. We then restricted access of knowledgeable birds to their less preferred side and calculated the latency until birds produced solutions as a measure of behavioural flexibility. A total of 22 of 23 knowledgeable birds produced at least one solution on their less preferred side after being restricted, with higher-frequency solvers being faster at doing so. In addition, 18 of the 23 birds reached their solving rate from prior to the restriction on their less preferred side, with birds with stronger prior side preference taking longer to do so. We therefore introduce and successfully test a new selective two-option puzzle box, providing detailed instructions and freely available software that allows reproducibility. It extends the functionality of existing systems by allowing fine-scale manipulations of individuals' actions and opens a large range of possibilities to study cognitive processes in wild animal populations.

An evaluation of the role of 'biological evidence' in zoo and aquarium enrichment practices

Evidence-based approaches are key to advancing all areas of zoo and aquarium practice. Output from empirical study must be disseminated to those within the industry so that results can support changes to husbandry and management for individual species. Information on enrichment techniques is published in a range of sources, including papers in the peer-reviewed and 'grey literature' (ie professional but non-reviewed publications). To investigate how evidence is implemented into enrichment practices, we sampled all enrichment studies identified in one online repository of peer-reviewed papers and two grey literature publications across an elevenyear period. We recorded whether the enrichment was supported with biological evidence (whether it was developed using published enrichment-focused research for that species and/or with the species' ecology and behaviour information) alongside analysis of the type of enrichment used and the chosen study species. Enrichment articles were more likely to be supported by biological evidence in peer-reviewed than grey literature. Taxonomic differences in the use of evidence were noted; for example, enrichment provided to carnivores and parrots was more likely to be supported with biological evidence compared to that used for penguins. Of the five enrichment types, nutritional enrichment was most often based on biological evidence. Multi-category and physical enrichment types were more common across all literature sources whereas social enrichment was less common, suggesting barriers to implementation of all enrichment types in zoological facilities. Our research suggests that zoo and aquarium professionals are considering species-specific welfare needs by ensuring that enrichment protocols are supported by biological evidence. However, opportunities to diversify the enrichment types being offered and species being researched are identified.

Do chimpanzees enjoy a virtual forest? A pilot investigation of the use of interactive art as a form of environmental enrichment for zoo-housed chimpanzees

Environmental enrichment is essential for the well-being of zoo animals. Recent advances in sensor and video technologies may contribute to improvements in enrichment in terms of their flexibilities and time constraints. The purpose of this study was to investigate whether interactive movie art can be used as a form of environmental enrichment. We implemented interactive movies designed by a professional artist, a visual art aiming to reflect naturalistic forest habitat, in an indoor chimpanzee enclosure at Kyoto City Zoo in Japan. Motion-tracking sensors embedded in buoys were installed at several locations around the indoor enclosure; the chimpanzees could change the movie contents by physically interacting with these objects. We recorded behaviors by observing entire troop of chimpanzees (six) between March 16 and 20, 2020 (control condition), then recorded behaviors when the interactive movie was presented (experimental condition) between March 21 and 29, 2020. Behaviors were recorded via direct observations and video recordings to examine any changes after the installation of interactive art. The chimpanzees spent more time in the indoor enclosures during the experimental condition than during the control condition. Activity budgets did not change substantially during the study period. There was no evidence of habituation to the movie during the study period. Three chimpanzees, including two young chimpanzees, interacted with the movie more frequently than the others; these young chimpanzees occasionally showed playful expressions when interacting with the movie and exhibited different reactivities to the movie scenes. These results demonstrate, first, that the interactive art did not negatively affect chimpanzee behavior, and second, that some of the chimpanzees indeed showed positive responses to the art. This study, therefore, introduces a novel possibility for environmental enrichment in zoos, involving a collaboration between science and art.

Use of Interactive Technology in Captive Great Ape Management

The conservation status of great apes (chimpanzees Pan troglodytes, gorillas Gorilla sp., orangutans Pongo sp., and bonobos Pan paniscus) is grave and zoological institutions are vital for maintaining numbers of these species and educating the public about their importance. Technology provides tools that can assist zoos in meeting these objectives. However, the extant research on technology use in zoos is potentially constrained by small sample sizes and there is no framework detailing the methodologies necessary for the successful incorporation of technology into great ape management. Therefore, this study aimed to determine current technology use in the management of captive great apes and whether technology-directed behaviour differs between ape genera. Primary carers of great apes in zoos were surveyed using a 43-question, online questionnaire. The purpose of integrating interactive technology into captive ape management was primarily for enrichment (53% of respondents), followed by research (20% of respondents). However, only 25% of respondents had apes directly engaged with technology. There were no differences in technology-directed behaviours between ape genera. By identifying differences in practice, this research marks the initial stage in developing a best practice framework for using technology.

Assessing the reliability of an automated method for measuring dominance hierarchy in non-human primates

Among animal societies, dominance is an important social factor that influences inter-individual relationships. However, assessing dominance hierarchy can be a time-consuming activity which is potentially impeded by environmental factors, difficulties in the recognition of animals, or disturbance of animals during data collection. Here we took advantage of novel devices, machines for automated learning and testing (MALT), designed primarily to study non-human primate cognition, to additionally measure the dominance hierarchy of a semi-free-ranging primate group. When working on a MALT, an animal can be replaced by another, which could reflect an asymmetric dominance relationship. To assess the reliability of our method, we analysed a sample of the automated conflicts with video scoring and found that 74% of these replacements included genuine forms of social displacements. In 10% of the cases, we did not identify social interactions and in the remaining 16% we observed affiliative contacts between the monkeys. We analysed months of daily use of MALT by up to 26 semi-free-ranging Tonkean macaques (Macaca tonkeana) and found that dominance relationships inferred from these interactions strongly correlated with the ones derived from observations of spontaneous agonistic interactions collected during the same time period. An optional filtering procedure designed to exclude chance-driven displacements or affiliative contacts suggests that the presence of 26% of these interactions in data sets did not impair the reliability of this new method. We demonstrate that this method can be used to assess the dynamics of both individual social status, and group-wide hierarchical stability longitudinally with minimal research labour. Further, it facilitates a continuous assessment of dominance hierarchies in captive groups, even during unpredictable environmental or challenging social events, which underlines the usefulness of this method for group management purposes. Altogether, this study supports the use of MALT as a reliable tool to automatically and dynamically assess dominance hierarchy within captive groups of non-human primates, including juveniles, under conditions in which such technology can be used.

Exploring How White-Faced Sakis Control Digital Visual Enrichment Systems

Simple Summary

Many zoo-housed primates use visual computer systems for enrichment but little is known about how monkeys would choose to control these devices. Here we investigate what visual enrichment white-faced saki monkeys would trigger and what effect these videos have on their behaviour. To study this, we built an interactive screen device that would trigger visual stimuli and track the sakis’ interactions when using the system. Over several weeks, we found that the sakis would trigger underwater and worm videos significantly more than animal, abstract art and forest videos, and the control condition of no-stimuli. Further, the sakis triggered the animal video significantly less often over all other conditions. Yet, viewing their interactions over time, the sakis’ usage of the device followed a bell curve, suggesting novelty and habituation factors. As such, it is unknown if the stumli or devices novelty and habituation caused the changes in the sakis interactions over time. These results also indicated that the different visual stimuli conditions significantly reduced the sakis’ scratching behaviour with the visual stimuli conditions compared to the control condition. Further, the usage of visual stimuli did not increase the sakis’ looking at and sitting in front of the screen behaviours. These results highlight problems in defining interactivity and screen usage with monkeys and screens from looking behaviours and proximity alone.

Abstract

Computer-enabled screen systems containing visual elements have long been employed with captive primates for assessing preference, reactions and for husbandry reasons. These screen systems typically play visual enrichment to primates without them choosing to trigger the system and without their consent. Yet, what videos primates, especially monkeys, would prefer to watch of their own volition and how to design computers and methods that allow choice is an open question. In this study, we designed and tested, over several weeks, an enrichment system that facilitates white-faced saki monkeys to trigger different visual stimuli in their regular zoo habitat while automatically logging and recording their interaction. By analysing this data, we show that the sakis triggered underwater and worm videos over the forest, abstract art, and animal videos, and a control condition of no-stimuli. We also note that the sakis used the device significantly less when playing animal videos compared to other conditions. Yet, plotting the data over time revealed an engagement bell curve suggesting confounding factors of novelty and habituation. As such, it is unknown if the stimuli or device usage curve caused the changes in the sakis interactions over time. Looking at the sakis’ behaviours and working with zoo personnel, we noted that the stimuli conditions resulted in significantly decreasing the sakis’ scratching behaviour. For the research community, this study builds on methods that allow animals to control computers in a zoo environment highlighting problems in quantifying animal interactions with computer devices.

An evaluation of interactive projections as digital enrichment for orangutans

Digital technologies are increasingly being incorporated into the provision of enrichment for captive primates, ranging from the ad-hoc use of iPads to specifically designed hardware installed in the design of new exhibits. In this article, we present a digital enrichment system that utilizes a novel approach with interactive projections, installed in the orangutan exhibit at Melbourne Zoo. While previous research into orangutan enrichment has involved reinforcement using food rewards, this study is the first investigation of digital enrichment for orangutans that does not involve food rewards. Rather, the interactive projections were designed to provide intrinsically rewarding environmental enrichment, instead of a cheaper or more variable way of delivering food. Our observations of orangutans' use of the system supports the approach of using interactive projections, finding that it is more responsive than capacitance or resistive based touch-screen technologies to the variety of ways that orangutans "touch": with whole hands, feet, faces, and with objects. We also present the results from a preliminary study into the effect of this enrichment into orangutan behavior which found presence or use of the device did not affect time spent engaged in the majority of behaviors of the individuals studied.

The Effect of Enrichment Filling and Engagement Time on Regurgitation and Reingestion Behaviour in Three Zoo-Housed Orangutans

Regurgitation and reingestion (R/R) is a prevalent, abnormal behaviour observed in captive great apes. R/R may be related to animal welfare and while less R/R appears to occur when apes are provided with browse and continuous foraging opportunities, the aetiology of the behaviour (e.g., foraging time or taste characteristics such as sweetness) is not well understood. This study aimed to determine how environmental enrichment may affect R/R in three zoo-housed, adult orangutans. Over eight weeks, nine fillable enrichment items were provided twice to each orangutan–once with a sweet filling and once with a savoury filling. Enrichment engagement time and R/R behaviour were monitored for 1-h after the item was provided. Individual differences were found in R/R occurrence. One individual was more likely to perform R/R when given enrichment with a sweet filling (p < 0.05), and a second was more likely to R/R with savoury filled enrichment (p < 0.05). R/R behaviour from the third orangutan was unaffected by enrichment filling (p > 0.05), however he engaged longer with savoury filled enrichment, compared to sweet (p < 0.05). No relationship was found between engagement time and amount of R/R behaviour, for any of the orangutans (p > 0.05). While these results should not be generalized without a larger study, they do suggest that diet and enrichment qualities may play a role in the performance of R/R, and individual variation should not be overlooked when considering causation.

Music for Monkeys: Building Methods to Design with White-Faced Sakis for Animal-Driven Audio Enrichment Devices

Simple Summary

Animals living in captivity can benefit from new forms of technological enrichment, with auditory enrichment currently being underutilized. Here, we investigate how to provide zoo-housed white-faced saki monkeys with auditory enrichment in an animal-centred manner. To study this, we prototyped and developed an interactive system that the sakis could trigger to play audio and that tracked their interactions with the device. Importantly, we incorporated this system into the regular living environment of the sakis and developed the interaction in a way that gave them control over activating the sounds. Based on the results, we conclude that audio is a promising way to provide enrichment for small primates like sakis. Utilising our device, we demonstrate that the sakis triggered the traffic audio more than silence, rain, zen, and electronic music, with no differences between the other conditions. However, we highlight problems in using this behaviour to infer the sakis preference or how they like the system, with further research needed towards sounds for audio enrichment. Our method reveals the value of collecting early real-world data and prototyping when designing interactive technologies for zoo-housed animals. In this experiment, we found that animal-centred methods can help create technologies better suited to their purpose and ultimately towards the end-goal of improving animal welfare.

Abstract

Computer systems for primates to listen to audio have been researched for a long time. However, there is a lack of investigations into what kind of sounds primates would prefer to listen to, how to quantify their preference, and how audio systems and methods can be designed in an animal-focused manner. One pressing question is, if given the choice to control an audio system, would or could primates use such a system. In this study, we design an audio enrichment prototype and method for white-faced sakis that allows them to listen to different sounds in their regular zoo habitat while automatically logging their interactions. Focusing on animal-centred design, this prototype was built from low fidelity testing of different forms within the sakis’ enclosure and gathering requirements from those who care for and view the animal. This process of designing in a participatory manner with the sakis resulted in an interactive system that was shown to be viable, non-invasive, highly interactive, and easy to use in a zoo habitat. Recordings of the sakis’ interactions demonstrated that the sakis triggered traffic audio more than silence, rain sounds, zen, and electronic music. The data and method also highlight the benefit of a longitudinal study within the animals’ own environment to mitigate against the novelty effect and the day-to-day varying rhythm of the animals and the zoo environment. This study builds on animal-centred methods and design paradigms to allow the monitoring of the animals’ behaviours in zoo environments, demonstrating that useful data can be yielded from primate-controlled devices. For the Animal-Computer Interaction community, this is the first audio enrichment system used in zoo contexts within the animals own environment over a long period of time that gives the primate control over their interactions and records this automatically.

High-Tech and Tactile: Cognitive Enrichment for Zoo-Housed Gorillas

The field of environmental enrichment for zoo animals, particularly great apes, has been revived by technological advancements such as touchscreen interfaces and motion sensors. However, direct animal-computer interaction (ACI) is impractical or undesirable for many zoos. We developed a modular cuboid puzzle maze for the troop of six Western lowland gorillas (Gorilla gorilla gorilla) at Bristol Zoo Gardens, United Kingdom. The gorillas could use their fingers or tools to interact with interconnected modules and remove food rewards. Twelve modules could be interchanged within the frame to create novel iterations with every trial. We took a screen-free approach to enrichment: substituting ACI for tactile, physically complex device components, in addition to hidden automatic sensors, and cameras to log device use. The current study evaluated the gorillas' behavioral responses to the device, and evaluated it as a form of "cognitive enrichment." Five out of six gorillas used the device, during monthly trials of 1 h duration, over a 6 month period. All users were female including two infants, and there were significant individual differences in duration of device use. The successful extraction of food rewards was only performed by the three tool-using gorillas. Device use did not diminish over time, and gorillas took turns to use the device alone or as one mother-infant dyad. Our results suggest that the device was a form of cognitive enrichment for the study troop because it allowed gorillas to solve novel challenges, and device use was not associated with behavioral indicators of stress or frustration. However, device exposure had no significant effects on gorilla activity budgets. The device has the potential to be a sustainable enrichment method in the long-term, tailored to individual gorilla skill levels and motivations. Our study represents a technological advancement for gorilla enrichment, an area which had been particularly overlooked until now. We wholly encourage the continued development of this physical maze system for other great apes under human care, with or without computer logging technology.

Relative response to digital tablet devices and painting as sensory enrichment in captive chimpanzees

Digital devices, including tablet computers and other touchscreens, can potentially serve as flexible and convenient means for providing behavioral enrichment activities to captive primates. Despite increased interest in incorporating technology into enrichment programs, no direct quantitative comparison has previously been made between the effectiveness of typical tactile enrichment activities and enrichment activities on digital devices. One way in which these activities differ is in the degree of controllability afforded the animals in interacting with the enrichment objects, since digital devices will be limiting to varying degrees based on the particulars of software and the interface format. This study compared the effects of painting with brush on paper to those of a painting application on a digital tablet device (iPad™) in eight group-living chimpanzees at the Honolulu Zoo. Observations were analyzed across baseline, enrichment, and post-enrichment periods to measure significant differences in the reduction of displacement and stereotypic behaviors. We found that the digital tablet device running an application that permits production of semi-automated visualizations, was as effective as painting with brush on paper in reducing some stereotypic and displacement behaviors, including yawning and self-picking. However, the digital tablet was not as effective in reducing other displacement behaviors, nor was it as effective in retaining the chimpanzee's attention. These results confirm a useful role for digital devices in enrichment programs but suggest a need to assess individual device applications in their capacity to promote greater controllability and sensory breadth of the enrichment experience.

Behaviour-Based Husbandry-A Holistic Approach to the Management of Abnormal Repetitive Behaviors

The field of zoo animal welfare science has developed significantly over recent years. However despite this progress in terms of scientific research, globally, zoo animals still face many welfare challenges. Recently, animal welfare frameworks such as the five domains or five needs have been developed and suggested to improve the welfare of zoo animals, but without practical guidance, such tools may remain abstract from the daily experience of zoo animals. Similarly specific practical strategies such as those for enrichment development exist, but their lack of holistic integration with other aspects of animal husbandry and behavioral medicine means that overall, good zoo animal welfare may still be lacking. This paper outlines some of the barriers to implementing improved zoo animal welfare in practice, and proposes a new strategy for the development of behavioral husbandry routines focused on the management and mitigation of abnormal repetitive behaviors. Focusing on enhancing zoo animal welfare by integrating aspects of ecology, ethology and clinical animal behavior into a practical and comprehensive approach to behavior-based husbandry.